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So I'm studying circuit design & I'm trying to determine where the Instruction Set prefixes are registered. surely the computer doesn't understand what mov means. Are they stored on a ROM with the associated logic circuits abstract states (wave functions) linked to them?

judofright
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    What is "instruction set prefix" supposed to mean? Do you mean *opcode?* There are many different ways this can be realised. Usually it's a whole bunch of random logic. – fuz Jun 23 '22 at 22:21
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    The processor understands the encoding for `mov`. Its job is to understand all the encodings for the instruction set. Most processors have most of this understanding hard coded into their circuitry, but microprogramming is an alternative; the two approaches are sometimes combined. – Erik Eidt Jun 23 '22 at 23:03
  • some processors are microcoded in some way and some are direct logic. The 6502 for example did have a rom, and the opcode byte addressed into the rom and the rom contained the microcode to control gates and muxes. but many others are just direct logic. and that logic would start off with interpreting the opcodes in the instruction and then working through additional parts of the instruction based on the initial decode. it is not magic in any way...quite simple (processors are very very dumb and simple) – old_timer Jun 23 '22 at 23:23

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